Ever since the first production of electrical circuitry there was a need to measure at least the voltage or potential and the amperage or current to see that all was functioning. With usage of the circuitry, especially on an automobile, wear and tear takes its toll and problems arise. In an attempt to remove these problems various testers have been marketed such as a volt ohm resistance meter or a live wire lighted probe. While these testers are helpful applicants device can expidite the locating of various problems such as short circuits and unwanted battery load.
While the prior art has revealed several multimeters the only ones even remotely close to applicants device are U.S. Pat. No. 4,791,376 and Canadian Patent 1,263,706. U.S. Pat. No. "376" describes a circuit tester that tests for the presence of voltage and uses a sound or light indicator however, it does not provide these functions by a full-wave rectifier with a relay across the rectifier to allow actuation of a buzzer in the event of non current flow through the relay. Canadian patent "706" is designed for ground fault detection in a system with a D.C. power supply and does have a LED display or sound indicator however, it requires a pulser to generate a pulsating ground fault signal and a magnetic sensor for detecting the location of the ground leakage current. There cannot be located in this patent applicants simple externally powered circuit of a full-wave rectifier with a relay across the rectifier to allow actuation of a buzzer in the event of non current flow through the relay. The above prior art is too complicated, too expensive and will not perform in the manner required by applicant.